Hewlett-Packard Corp. (NYSE: HPQ) continues to lead the PC market in sales, and the addition of a laptop model that will run an unprecedented 24 hours on a single battery charge may boost its fortunes even more. The holy grail for those who use portable electronics constantly is battery life. Although battery technology has improved in the last decade or so, the ever-increasing demands from portable electronics like cellphones and laptops mean smaller battery times and more recharging.

HP's new EliteBook 6930p will cost anywhere from $1,800 to $2,000 online, and will come with an optional battery and a solid-state disk drive to help it get to the specified 24-hour battery life (which is probably ultra best-cast scenario). Dell's recently-announced Latitude E6400 reportedly sees 19 hours on a single charge. Perhaps the consumer and business PC markets are about to see a shift away from being compared on their commodity parts to something that really matters to most users -- battery life.

With PCs accounting for a third of HP's total revenue, it's the $30 billion question the company has to ask -- how can it keep growing that segment of its business? Desktop PCs, also at work, are slowly being replaced with laptops -- allowing workers to work from anywhere, the goal of the corporate kingdom -- and laptops are slowly but surely making the standard desktop PC irrelevant.

But that comes with a price: battery life really needs a boost. After all, the definition of a laptop basically implies that the customer needn't be tied to a power outlet at all times. In HP's case, the new laptop only costs $1,200 before the optional $150 extended battery and the $900 solid state disk drive. Are those items worth the price to get an entire day of battery life, though? Sales of the new system will tell us.